Winding machine



March 29, 1960 w. v. GOODHUE ET AL 2,930,543

WINDING MACHINE Original Filed April 26, 1951 2 Sheets-Sheet 1 INVENTOWILLIAM V. 600 UE By FRANK w. HIGGINS AT TORNE Y March 29, 1960 w. v.GOODHUE ET AL 2,930,543

WINDING MACHINE Original Filed April 26, 1951 '2 Sheets-Sheet 2 III/IIVIIIIIIIII 52172121 0119: WILLIAM V. GOODHUE FRANK w. HIGGINS 2,930,543WINDING MACHINE William V. Goodhue, North Kingstown, Rl, and Frank W.Higgins, Wareham, Mass., assignors to Leesona Corporation, a corporationof Massachusetts Claims. (Cl. 242-150),

This invention relates to winding machines for wind in'g yarn or likestrandular materials into cops, cones and other forms of packages and isa division of our copending application Serial No. 223,022, filed April26, 1951, now Patent No. 2,764,362.

In the present specification and claims the term yarn is used in ageneral sense to designate all types of attenuated materials and theterm package is employed for convenience of description to apply to anyusual form of wound mass. I

One object is to provide in a machine of the type indicated means foropening the tension-device to receive the new end and means for openingthe slub-catchers.

Another object is to provide in a machine of the type indicated meansfor applying jets of air to the tensiondevice'and slub-catchers as theyare opened whereby to remove the lint, flulf or other foreign particlestherefrom and valve-means for automatically operating the jets.

Further objects of the invention are set forth in the followingspecification which describes a preferred form of construction of thepresent invention by way of example as illustrated by the accompanyingdrawings. the drawings:

Fig. 1 is a perspective view illustrating the tension assembly of thepresent invention mounted in its operating position on the frame of awinding machine of the type disclosed in United States Patent No.2,764,362;

Fig. 2 is a plan view of the tension-assembly including the pairofslub-catchers and the means for cleaning. the elements with air-jets;1

Fig. 3 is a part-sectional side elevational view of the tension-assemblytaken on line 7-7 of Fig. 2;

Figs. 4 and 5 are detailed views of the tension-device and the means forshifting the reserve supply yarn into position to be picked up by thetension-nozzle;

Figs. 6 and 7 are part-sectional detailed views of the same;

Fig. 8 is a fragmentary bottom plan view of one of the operating shaftsof the tension-assembly; and

Fig. 9 is a part-sectional view in elevation showing the means foropening the slub-catchers. I

In a winding machine of the type disclosed in said Patent No. 2,764,362means for retaining spare yarn end in reserve; means for threading thespare yarn between tension-disks; and the other instrumentalitiescooperating therewith are mounted in a group, called the tension,-assembly, which is carried by a bracket 39 projecting forwardly from theframe which in turn is mounted on bed 2. The tension-assembly mountingconsists in a relatively flat panel 40 supported in inclinedrelationship by the bracket 39 that is bolted to a U-shaped yoke 41fastened to the sides of the frame 20 of a winding machine. Fastened tothe forward end of the panel 40 is a yarnguide inthe form of a plate 42having its lower portion curved inwardly angi rearwardly. 'The upperportion of the guide-plate 42 is formed with a slot 43 having areentrantopening at the top and extending downwardlyat an; a e w t a e aire ys o om ro t oa 45- at.

' nited States Fatent" ingthe yarn y to slide down into positionacrossitsver:

0 at the side of the tapered finger the bottom. The right-hand edge ofthe slot 43 recedes arcuately toward the top of the plate 42 while tothe left of the re-entrant opening of the slot is an upstanding finger44 tapered to a rounded point at the top; The running yarn y is guidedin the lateral extension 45 at the lower end of the slot 43 in the plate42 as it feeds to the tension-device and thence to the winding package;while the spare end y is normally held in reserve on a rest 46 formed bya shoulder on the edge of the slot 43 44, being retained in this reserveposition by the arcuate edge of a detention lever 47.

The detention lever 47 is mounted fast on the forward flatted portion ofa rod or rock-shaft 50 which extends longitudinally beneath the panel 40with its terminal portions rotatable in suitable bearings at the endsthereof. A second rock-shaft 51 is similarly mounted in bearings on theunder side of the panel 40 in parallel spaced relation to the shaft 50.These two shafts 50 and 51 carry the several elements which functioncooperatively for threading the spare end y down into the guiding slot45 of the plate 42 and also into the tension-device during consists inan elbow-shaped arm, see Fig. 4, extending laterally from a hubportion52fast on the rock-shaft 50 and rising upwardly in a skeleton headhaving a vertical arm and a curved portion 53 fonning'it's arcuate edge.With the lever 47 in normal position as illustrated in Fig. 4 thearcuate edge of its curved portion 53 cooperates with the edge of thetapered finger 44 to form a sort of crotch for retaining three in numberas herein single hub-portion 62 fastened to the rock-shaft 50, see Figs.1, 2 and 3. The horizontal arms of the fingers 61 are normally supportedslightly above the yarn y feeding across the bars of the grid 60, beingsustained in this relationship by latching means, as described in UnitedStates Patent No. 2,764,362, which act to prevent the shaft 50 fromrocking. The detectorshown, extending from a fingers 61 have angularextensions 63 projecting upwardly;

66 is formed with a slot 68 through which the screw 67- extends. Theguide-member 65 comprises an upright blade with an inclined upper edgewhich assists in cans- 51 after the yarn y'from the.

in place by one of the screws.

' genesis tical edge, thereby serving to retain it in the tensiondevice.

The tension-device may comprise the usual concavoconvex disks 70rotatably mounted on a pin 71 which is slidablethrough the bore of aboss 72 on the under side of the-panel 40. The pin 71 has a shoulderedenlargement 73, see Fig. 5, located in position to engage with and liftone or more weights 74 which apply pressure to the upper disk 70,whereby to relieve the pressure thereon as the yarn is threaded into thetension-device. The weight 74 normally bears against a felt washer 75 topress the upper tension-disk towards the lower disk and apply resistanceto the passage of the yarn therebetween. A helical spring 76 encirclingthe pin 71 between asplit ring 77 and the bearing boss 72 acts tonormally draw the pin downwardly.

Mounted fast on the opposite rock-shaft 51 is a lever 80 arranged withits end engaging under the end of the pin 71 to adapt it to slide thepin upwardly against the tension of the spring 76, whereby to remove thepressure of the weight 74 on the upper tension-disk 70 and thereby openthe tension-device for threading the yarn between the disks. Means areprovided for cleaning the tension-disks when they are thus opened byblowing lint or any other foreign particles therefrom. The tension-disks70 are cleaned by air-jets projected from a tube 82 having asemicircular portion partially surrounding the periphery of the disks.and provided with small orifices (not shown) on its side for emission ofthe air forced through the tube. The semicircular portion of the tube 82serves as a guide for directing the yarn into place between thetension-disks 70 and has an extension 83 projecting upwardly at one endand terminating in a loop at the top. This extension 83 of the tube 82serves as a guard to direct the yarn down under its semi-circularportion. The upper end of the tube extension 83 is also provided with anorifice for projecting an air-jet across the detector-fingers 61 toremove the lint accumulation therefrom. A straight length of the tube 82is supported in a lug 84 rising from the side of the panel 40 with theend of the tube projecting therefrom and connected to a flexible hose 85through which the'air is supplied. The air-hose 85 is connected to apipe-T 86 on the side of the bracket 39, see Fig. 1, and thence to avalve 92 in the supply line from a suitable source of compressed air,not herein shown.

A branch hose 87 from the T 86 extends across the underside of the panel40 for connection to another tube 88 employed for cleaning theslub-catchers mounted at the rearward end of the panel 40. The'slub-catcher cleaning tube 88 overlies the side of the panel 40with alength bent downwardly and fastened at its end to a union 89 mounted onthe bracket 39. The tube 88 may be fastened to the panel 40 by a clamp90. The branch hose 87 which extends from the three-way pipe-T 86 isconnected to the union 89. From the pipe-T 86 a hose 91 leads to theair-valve 92 shown in Fig. l. The airvalve 92 may be of any suitableconstruction, preferably of the plunger-operated type as illustrated inFig. 1, with its plunger 93 adapted to be forced downwardly by lever 433through link 432 to open the valve through the operation of certaininstrumentalities as described in United States Patent No. 2,764,362.

Mounted at the rearward or upper end of the panel 40 is a pair ofslub-catchers 95, see Figs. 1,2 and 3, for cleaning theyar'n before itfeeds to the winding pack; age. The slub-catchers 95 areof usualconstruction, each comprising a lo'wer fixedblade 97 and an upper hingedblade 98 pivoted on a rod 99 with a spring 100 for rock; ing the upperblade to maintain its lower edg'e'in sp'aeed relation to the edge of thelower blade. The rods99 are supported in bearings 101 on standards 102formed as a part of the panel 40. The upper blade 98 of eachslub-catcher has an arm 103 projecting "at the letters; viewed in Figs.2 and 9 "and overlying the ender plunger-pin 105. which is slidable inthe bore of a bearing forming part of the standard 102. The lower end ofthe plunger-pin 105 is engaged by the end of a lever 107, see detailedview Fig. 9, secured fast on the rock-shaft 51 so that when the latteris toeked the lever 107 will slide the pin upwardly and thereby rock theupper blade 98 of the slub-catcher 95 to open the latter as shown inFig. 3 torthreading the yarn thereinto. When opened the slub-catchersare cleaned by air-jets emitted from the tube 88, previously referred toas connected through the union 89 and pipe-T 86 to the hose 91 from thevalve 92, see Fig. 2. The tube 88 has iet'orifice's on its side directedtoward the openings between the blades of the slub-catchers 95. Anotherorifice at the bend in the tube 88 causes an air-jet to be ejectedtherefrom along the crossbar 633 of the breakage-lever 625 to remove anylength of yarn tending to cling thereto when the yarn is broken.

Supported rearwardly beyond the sluts-catchers 95 is a plate-like guard115 fastened to the rearward standard 102 with its lower rounded edge inposition to adapt the yarn to feed thereunder. Beyond the edge of theguard 115 is a wire bail 116 arranged parallel therewith and under whichthe yarn feeds, the wire having a rightangular bent portion fastened ina bore at the end of the panel 40.

It has been stated that the end of the spare yarn y is held in reserveresting on the shoulder 46 in the guidethe clip lever 120 carfie's aplate 42, see Fig. 1, and retained in place by the lever 47. A transferlever 120, see Fig. 7, mounted to turn on the rock-shaft 51, extendsupwardly therefrom through an opening in the panel 40, being providedwith a clip 121 at its upper end for seizing the end of the reserve yarny. The lower end of the lever 120 has a bifurcated hub-portion withbores in its bifurcations that serve as bearings for pivotallysupporting the lever on the rockshaft 51. The upper terminal portion ofthe lever 120 is bent outwardly at an angle to adapt it to cooperatewith a reversely-bent angular extension of the clip 121, thus forming acrotch therebetween into which the end of the yarn y may be inserted and'carried down between the main arm of the lever-and the parallelportionof the clip .to grip it therein. The clip 121 is rockably mountedon the upright arm of the lever 120 by means of its laterally-projectingfinger 122 engaging loosely through a slot in the arm. A leaf-spring 123fastened to the rearward side of the lever 120 with its offset portionbearing against the back of the clip 121 :tends to hold the latterpressed against the yarn y to' bind it to the lever. The clip-lever 120is normally held cocked in upright relationship as shown' in Fig. 11 bylatching means arranged below the panel 40 "and mounted on the oppositerock-shaft 50. t

A helical spring 125, see Fig. 8, is coiled around the rock-shaft 51 andhas one end engaged across a portion of the panel 40 with its other endhooked through a hole in one of the bifurcations of the hub of the lever120. The spring 125 acts to rock the clip-lever 120 downwardly towardthe top of the panel 40 to draw the end of the reserve yarn y into placeto thread it between the tension-disks 70. Moverrient of the lever H20in this direction is limitedby the end of a stud 126 in the side as thebracket 39, see" Fig. 6, engaging with the bent end- 127 of adownwardly-exteiiding' latchingarm-128 on the lever 120. The ii'pri'ghtportion of 'laterally extending wire rod 1 29 terminating in a-right-ang'ular en's'ioii 130, this .rod being used for rockinginsane-lever upwai dly and rearwardly to latchit in its up'r i"htpbsition-in the manner later explained. v

-Referring to'Figs. '6"*an'd' 7. a latching lever 1 35 has itsbifurcated hub-portion' secufed Tast on the foclishaft se. The pper arm136 of the "latbhinglever 13's is inclined downward and-then upwardlynear-it ms in a sert er rok-, the refiner assass ns-"w nesis-adat to beengaged by the right-angular bent-end 127 of the latching arm 128 on theis swung back into upright position to cock it in this relationship.Projecting downwardly from the upper arm 136 of the latching lever 135is a vertical extension 137 carrying a bent or crooked arm 138 shapedlike the end of the upper arm but somewhat shorter. The bent end 127 ofthe latching ann 128 on the clip-lever 120 is adapted to engage with theunder edge of the bent end of the upper arm 136 of the latching lever135 to raise the latter and permit the end of the latching arm to enterbetween the two arms 136 and 138 of the latching lever and be held bythe crook in its lower arm, see Fig. 7, against the force of the coiledspring 125 on the shaft 51. The latching lever 135 is maintained raisedin engagement with the latching arm 128 on the clip-lever 120 by meansof a hooked lever 140 having a bifurcated hub-portion rotatably mountedon the rockshaft 51 and normally held in the position shown in Fig. 7under the tension of a spring 141 coiled around theshaft 51, see Fig. 8.A stud 142 supported in an ear 143 on the upper arm 144 of the lever 140with its end adapted to engage against the top of the panel 40 acts tolimit the rocking motion of said lever 140 under the tension of thespring 141. The hooked end of the lever 140 terminates in an inclinedcam-edge 145 adapted to slidably engage with a finger 146 projectinglaterally from the lower portion of the latching lever 135 and therebycause said finger to enter into locking engagement with the hooked endof said lever 140, see Fig. 7, to maintain the clip-lever 120 latched inupright posit-ion. A lever 147 has its bifurcated hub-portion securedfast on the rock-shaft 51 by a screw 148 and terminates in aright-angular bent arm 149, see Fig. 8. The arm 149 overlies the upperportion of the lever 140 to rock it downwardly so as to cause the finger146 to be released from the cam-edge 145 of the lever 140'.

The release of the latching means for the yarn-clip lever 120 iseiiected by the operation of a cam-lever 150 mounted fast on the shaft51 and employed for rocking the latter. As shown most clearly in Fig. 6,the cam-lever 150 consists of a U-shaped wire arm 151 having oneterminal portion bent around the rock-shaft 51 and secured fixedlythereto by means of a binderscrew 152. The opposite end of the U-shapedlever 150 has fastened thereto a cam-plate 153 of substantiallyovateshape in outline. The upper edge of the camplate 153 is of arcuatecontour extending inwardly towards the center of the panel 40 with itsunder edge of reversely-curved contour and joining the upper edge in acircular end. The cam-lever 150 is actuated to oscilheld by the clip121'on the lever' l20 when the latter i s inlits depressed relationshipshown'in Fig. 6; The end of the tension-nozzle 155 continues its"movement from the cam -plate 153 to engage the laterally-extending rod129 on the clip-lever120 and rock the latter into up ight position,thereby cocking ,it to be held by its latching means described above.

Cami-plate 153'alongits curved edge to "lift the lever 150 and oscillatethe lever 80 on slide the pin-71 upwardly for raising the weight 74 fromthe clip-lever 120' when the latte'r On the return motion: ifthetension-nozzle 155 the finger 180 rides under the t I the rock-shaft 51to ppe'r'tension-disk 70- inthe manner and for the pur sesame,

the clip-lever posemore fully explained in-United States Patent. No.2.764.362. Q

The foregoing mechanism operates in the following described manner:

The yarn y from a bobbin or other suitable source of supply, supportedtherebelow but not herein illustrated, is drawn up and entered in theguide slot 45 of the end-plate 42 on the tension-assembly, see Fig. 1,then led under the slack-lever 55 and the detector-fingers 61 to lieacross the bars of the grid 60. The yarn y is then carried down alongthe vertical extension 83' of the tubular guide 82 to cause it to drawunder the circular portion of the guide and enter between the contactingfaces of the tension-disks 70. From the tensiondisks 70 the yarn isentered between the blades of the dual slu-b-catchers 95, and under thelower edge of the guide-plate 115, thence above the crossbar 633 of thebreakage lever 625 and under the horizontal portion of the wire guide116. From the tension-assembly the yarn is led upwardly to a windingmachine preferably of the type disclosed in United States Patent No.2,764,362.

A spare or reserve yarn y supplied from another bobbin arranged below isled upwardly therefrom and carried across the shoulder 46 onthe guideplate 42, thence across the slack-lever 55 in its notch 57 and finallyto where its end is engaged in the springclip 121, see Fig. 7, to holdthe strand under tension.

During the interval that the slub-catcherblades 98 are held open by thelevers 1'07 and whilethe tension-disks 70 are separated slightly thepneumatic means are operated to release jets of air from the supplypipes 82 and 88, see Fig. 2, for cleaning these parts. This isaccomplished by opening the valve 92 on the side of the frame 20, seeFig. 1, during the downward rocking motion of the lever 433, previouslyreferred to, to cause the stud 588 to depress the plunger 93 and openthe valve 92. A suitable source of compressed air is supplied to thevalve 92 through the pipe 94, shown in Fig.

1, so that jets are emitted from the side of the pipe 88 blades of theslubcatchers 9'5; and a series of jets from the circular portion of thepipe 82 are sprayed across the opposed faces of the tension-disks 70 toclean the lint and other foreign matter from their surfaces.

from an orifice in the end ing its return movement the lovers 107 andthe lever 30,

which have opened the slub-catchers and tension-device are both returnedto first position as the cam-lever drops back to its normalrelationship. The pivoted blades 98 of the slob-catchers 95 thecam-lever 150 has been depressed. As the mouth 1'81 rides along the camthe lever 150 so that the shaft 51 is rocked in clockwise of the nozzleswingsto ward the center ofthe tension-assernbly the finger 153- anddepresses guide-tube 82 to sense" v 7 Fig. 7, and rock edge 145 from thefinger 146 on the latching lever 1 35. As the latching lever 135 isreleased in this manner gravity causes it to swing downwardly into theposition shown in Fig. 6, thereby rocking the shaft 50 incontraclockwise direction. The detector-fingers 63 will then be swungdown through the slots in the grid 60, since no yarn remains thereunderto sustain them. As the shaft 50 is rocked contraclockwi'se thedetentionlever 47 will likewise swing downwardly, see Fig. 5, to causeits end to pass under the yarn if for releasing it to enter the slot 43in the guide-plate 442 shown in Pig. 1. At this point the notchedshoulder 57 on the slacklever 55 applies a drag on the yarn and as thelever swings downwardly it takes up any slack in the yarn. Meanwhile,the lower arm 138 ofth'e latching lever 135, see Fig. 7, has releasedthe latching arm 123 to cause the latter to swing into the positionshown in Fig. 6 and engage against the limiting stud 126. The clip-lever120 is thus released to cause its spring 125 to rock it downwardly andcarry the end of the yarn y held inthe clip 121 into position to besucked into the mouth of the nozzle 155 as the latter continues itsmovement along the cam 1-53 on the lever 150. As the clip-lever 1'20 isswung downwardly in this manner it will draw the yarn y laterally v 82at the side of the tension-disks 70. Continued movement of thesuction-nozzle 155 while its cap 181 is still open will cause the yarnto be sucked into the nozzle and as soon as the finger 180 on the caprides off from the end of the cam 153 the cap will be closed by thesuction to seize the yarn y against the mouth of the nozzle.

As before explained, the tension-nozzle 155 continues its movementacross the tension-assembly to engage it with the rod 129 on theclip-lever 120 and swing said lever back slightly beyond its verticalposition to cause it to be cocked by the latching means. When thecliplever 12!) is rocked in contraclockwi-se direction against thetension of its spring 125 its latching arm 12%; is swung upwardly and asthe finger 180 on the cap 131 rides off from the end of the cam 153 thespring 141, see Fig. 8, rocks the hooked lever 140 and shaft 51contraclockwise to engage 149 of the lever 147. The hooked lever 140 isthus swung upwardly to cause the end of its hooked portion to contactthe finger 146 on the lever 145, see Fig. 6. Continued movement of thenozzle 155 against the rod 129 on the clip-lever 120 will swingthe bentend 127 of the latching arm 128 against the upper arm 136 of thelatching lever 135 to rock it in clockwise direction and cause thefinger 146 to slide off from the end of the hooked lever 140 and engagethe cam-edge 145, see Fig. 7, to retain the shaft 50 in its initialposition. As the shaft 50 is rocked clockwise the detention-lever 47,the slack-yarn take-up lever 55, and the detector-fingers 63 will alsobe rocked clockwise to restore them to initial position. At thisjuncture the clip-lever 129 will have rocked to its extreme rearwardposition and the nozzle 155 will have completed its movement across thetensionassembly. Then as the nozzle 155 starts to swing back in theopposite direction the clip-lever 125) is released so that the latchingarm 128 will be rocked downwardly to engage it's bent end 127 "acrossthe lower arm 13% of the latching lever "135 as shown in Fig. 7 to holdthe cliplever cooked in vertical position. During the movement of thenozzle 155 back towards the knotter the spare yarn y" w'illbe drawnunder the circular portion of the thread it between the tensiondisks 70,and as the yarn lides'along the upper edge'of the guidemember 65 anddown "across its vertical edge it will be drawn in under thedetector-fingers 63 to the delivering position 'sh'owniniFi'g. 2.

With the tension assembgly elements restored to initial position a freshbobbin is sup lied, the yarn therefrom the latter downwardly to releaseits can against the upright extensio n 83 of the guide the lever withthe bent endthreaded through the guiding means and its end 851 to makeit ready tened in the clip 121 on the lever for retrieving and joiningto the end on the package when the previously-joined end is exhaustedfrom the supply bobbin.

While the machine is herein shown and described as embodied in apreferred form of construction, modifications may be made in thestructure and arrangement of its mechanisms within the scope of theinvention as expressed in the following claims. Therefore, withoutlimiting ourselves in this respect, we claim:

1. In a winding machine having means for rotating a package to wind yarnthereon, a tension-device for applying tension to the yarn feeding tothe package, a' tube disposed adjacent the tension-device and havingjetorificcs on its side, means connecting said tube with a source ofcompressed air, a valve for controlling the admission of air to thetube, and means operable in the absence of yarn to be wound to open thevalve to cause jets of air to be emitted from the tube to remove lintand other foreign particles from the tension-device.

2. In a winding machine having means for rotating a package to wind yarnthereon, a tension-device comprising associated members for engaging theyarn feeding to the package to apply tension thereto, means to separatesaid members to open the tension-device, to tube disposed adjacent saidtension-members and provided with orifices on its side, and means tosupply compressed air to said tube to cause jets of air to be emittedthrough the orifices in the tube to remove lint and other foreignparticles from the tension-members while they are separated.

3. In a winding machine having means for rotatably supporting a packageto wind yarn thereon, a tensiondevice having associated disks betweenwhich the yarn feeds to apply tension thereto, means for rotatablysupporting the tension-disks, a weight for applying pressure to one ofthe disks, means for lifting the weight to release the pressure on saiddisk, a tubular member disposed circumferentially of said disks andformed with orifices on its side, and means to supply compressed air tothe tubular member to cause jets of air to be emitted therefrom betweenthe tension-disks to remove lint and other foreign particles therefromwhile said one disk is free of pressure.

4. In a winding machine having means for rotatably supporting a packageto wind yarn thereon, the combination therewith of a tension-assemblycomprising a pair of tension-disks between which the yarn feeds to thepackage, a grid comprising spaced bars across which the yarn draws infeeding to the tension-device mounted in close proximity to said tensionassembly, feeler-fingers arranged above said grid, a tube including anarcuate portion surrounding the tension-device and an upstandingextension, said tube having at least one orifice in said arcuate portiondirected towards said assembly and at least one orifice in saidextension directed towards said grid, and means for supplying air to thetube to cause jets to be emitted through said orifices to remove lintand other particles from both the tension-device and grid.

5. In a winding machine having means for rotating 1; package to windyarn thereon, the combination therewith of a tension-assembly includinga pair of tension? disks, means for opening said disks a slub-catcherfor cleaning the yarn as it feeds from the tension-device to thepackage, means for opening of compressed air, .a tube extending adjacentthe tensiondevice and formed with orifices in its wall directed towardssaid tension assembly, a tube located adjacent the slub-catcher andhaving orifices directed towards said stub-catcher, means for connectingsaid tubes with a source of compressed air, a valve, and meansforopening the valve to admit eZair to both the tubes-simultaneously andcauses jets to be emitted from said orifices the slab-catcher, asourcefor cleaning the tension-device same are open.

and dub-catcher while the Glazier et a1. Vickers Anderson Ian. 30, 1923June 17, 1924 Oct. 11, 1932 10 Winslow -1 Feb. 17, 1942 Brngger Mar. 16,1948 Bdrtholomew Sept. 28, 1948 Swanson Dec. 23, 1952 Heizer et al. Dec.8, 1953 Klein Mar. 13, 1956 FOREIGN PATENTS France Apr. 8, 1953

